GreenD
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A patent claiming 60-80% efficiency in solar energy
I'm reading this patent, and I can't help but call bullshit. There isn't much to the patent itself - it is very vague.
http://www.freepatentsonline.com/4574161.pdf
It claims to have some type of linear dipole crystal called a Lepcon, a commercial name for the product, but does not really explain what the crystal
is. It makes a claim that it is manufactured the same way as polarizing polymers...
Anyone want to dive in and help me in debunking this, or possibly finding something that should be on the market today (the patent is from '86!)
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not_important
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Also see http://www.freepatentsonline.com/4720642.pdf
this has been floating around for awhile, claims to directly "receive" visible light photons as one does with RF wavelengths, then rectify the AC.
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GreenD
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I'm not sure I'm understanding the work functions correctly;
They say a work function between to metals...
Actually, I don't understand any of it. I would like to, though.
The patent I put up, I believe, according to one diagram, works on the theory of an electron reflecting back and forth on a cylinder. At one end there
is an insulator of a small thickness, with which the electron has a probability of passing through. Since the electron continuously is being reflected
between the two surfaces without loss of energy (why is there no loss?) yet has a possibility to jump an insulated gap, it therefore is able to
partake in a voltage increase, essentially entering a circuit where work can be done with it...
This seems simple in theory, but I am wrought with questions on it's actual ability to work on a scale or magnitude of the sun's rays...
Any personal opinions / clarifications / explanations?
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Twospoons
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the efficiency claim probably only applies for a single wavelength. The same issue occurs with photovoltaic cells - if you want broadband efficiency
you need multiple layers tuned to the various incoming wavelengths.
Helicopter: "helico" -> spiral, "pter" -> with wings
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m1tanker78
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Sorry, I haven't looked through the patents that were referenced. Twospoons made a good point about the efficiency claim probably belonging to a
narrow or single band. It sounds comparable to what one could achieve with a proper waveguide.
In short, a waveguide is employed to transmit EM waves of a specific wavelength (frequency) while greatly attenuating off-band signals (harmonics are
a bitch, though). A carefully engineered waveguide offers low loss and can be made to either match or alter the impedance.
The 'business end' of a RF waveguide can be as simple as a loop of wire. I'd imagine that one could capture and convert almost any wavelength from
A.M. on up to gamma rays and such from the sun. The atmosphere is opaque to some wavelengths so those are automatically out (unless the device is
destined for a satellite or space probe). Waveguides below MW frequencies tend to be very large. A waveguide for the visible spectrum would present
the same challenges that we face today with PV cells. One advantage of a visible WL waveguide may lie in the ability to transfer more light to a
multi-layer PV cell.
Regardless, the only [theoretical] efficient solar cell is one that can capture ALL the wavelengths and convert that energy to a usable form. AFAIK,
that's a very long way away yet. 
Tank
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White Yeti
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I call bullshit on this as well. The Carnot efficiency limit for solar cells is ~80%. This guy is claiming to have made a solar cell whose efficiency
is extremely close to the the theoretical limit. We all know that there are limitations everywhere. It's nearly impossible to achieve 100% efficiency
(I'm referring to 100% of 80%, not of 100%).
But there's one problem, solar cells are also subject to a different efficiency limit, the quantum efficiency limit, which I believe is around 60%
(correct me if I'm wrong).
Also, one last thing, the fact that the author claims to have made a solar cell with such a wide efficiency range, indicates that his product does not
work. The only way you can really change the efficiency of a solar cell, is by modifying the frequencies of incoming light.
Hope this helped.
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not_important
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While I'm skeptical of the claims, I must point out that properly the Carnot Limit applies to heat engines; photovoltaics and fuel cells are not heat
engines per say, although they do have (other) maximum efficiency limits.
As I said, these are old and IO believe expired (1988 + 20 years), if they were practical one would expect to see commercial applications. I remember
seeing these concept toted a few years ago as a way to utilise thermal radiation as an energy source, seemingly ignoring the laws of thermodynamics.
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